The invention relates to a process for the storage and dumping of waste materials having constituents which are subject to elution and emission under ambient conditions.
Various factors such as the sudden increase in the amounts of commercial and private waste, the increasing scarcity of disposal sites and the development of an environmental consciousness have, over the past few years, contributed to increasingly stricter regulations regarding waste disposal. These regulations are particularly strict in connection with so-called "special waste", formed by waste from industrial and other undertakings, which is particularly damaging to the environment. Therefore, in current waste disposal laws, additional requirements are made in connection with the disposal of waste from industrial or other undertakings, which on the basis of type, quality or quantity is particularly prejudicial to health, water or air supplies, or which is explosive or flammable or which contains carriers for communicable diseases. In general, such special waste cannot be disposed of with general refuse. The term "special waste" is used due to the particular danger caused to the environment.
Considerable problems are caused particularly by special waste which contains constituents which can be eluted and/or emitted under ambient conditions. Thus, for example, there are long term risks to the environment, due to leaching out and the collapse of drums etc., when special waste containing more than 10% water-soluble constituents is stored in above-ground dumps. Rainfall gradually elutes the special waste stored in dumps. Large quantities of salts and heavy metals are concentrated in the ground water. The toxic heavy metals have to be precipitated by costly treatment. The dissolved salts, whose removal is only made possible by very costly evaporation or ion exchange processes, generally pass in an unchanged state through the biological purification plants and increase the salt content of the affected drainage ditches and rivers.
A further problem in special waste dumps is that the deposited materials are frequently not compact. However, adequate compacting is necessary to provide an adequate strength so that vehicles can pass over the materials, and the latter must be able to take the extra load. Therefore, sludge-like or paste-like special waste must often be brought into a compact consistency, which involves considerable expenditure and for which lime, sawdust and other binders are used.
A special problem is caused by emitting special waste materials, which give off gaseous, liquid or pulverulent constituents into the environment and which therefore frequently constitute a serious hazard or at least annoyance. This applies more particularly to toxic special waste.
Special waste which reacts with water, such as magnesium waste and acid chlorides may not be stored in open special waste dumps. Thus, such special waste requires costly disposal or storage in closed containers. For safety reasons, acid and alkaline waste materials should not be stored together, because they can violently react with one another.
The purpose of this invention is to improve the process described hereinbefore so that the deposited material undergoes virtually no elution, the emission of noxious substances is prevented, even when paste and sludge like waste is removed, the stored material retains a high bearing capacity, reactions between the different waste materials and with the environment are prevented and an optimum compact storage of the waste is ensured. Particular importance is also attached to the economic aspects of the process.
According to the invention, these problems are solved when the waste materials are mixed with:
(a) a water-repelling, thermoplastic, melted binder, or PA0 (b) a binder which hardens through chemical reaction, which is water-repelling in the reacted state, and in the presence of a hardening agent,
and in the pourable or fluid state the mixture obtained is directly introduced into a dumping area where it is made to solidify or harden, or is initally placed in a mold where it is hardened or solidified and, optionally after stripping, is then introduced into a dumping area.